Psoriasis is a chronic skin disease which progresses gradually, the main signs and symptoms of which are papulosquamous and itching. Psoriasis includes the presence of small elevations of the skin that may be characterized as elevated red lesions, plaques or pustules on the skin which eventually result in silvery scales. These silvery scales and plaque are the result of accelerated epidermal proliferation and the metabolic activity and proliferation of capillaries in the dermal region and the invasion of the dermis and epidermis by inflammatory cells. More specifically, the capillaries in the dermal region become tortuous and dilated as well as suffer an inflammatory reaction causing the skin to redden.
The exact mechanism which triggers the abnormal cell proliferation is not known, though it is believed that there may be biochemical stimuli and environmental factors. The severity and course of psoriasis can vary greatly depending on the individual, but in general this chronic skin condition recurs throughout the life of the individual with varying intervals of one month to many years.
The formulations to be used are limited to the most common preparations such as, solutions, creams, and salves, in which, the manner of application for the dermatherapy is practically predetermined. Historically, psoriasis has been treated topically with coal tar derivatives as well as salicylic acid with limited success. Corticosteroids and other similar drugs have been found effective for serious cases of psoriasis. Unfortunately many of these drugs produce serious side effects, and in some cases once the drugs are discontinued, the psoriasis recurs with marked exacerbation.
The Wrightia tinctoria R. Brown var. laevis is a tree which can grow up to 40 meters tall and has a dark gray bark. The stalk at which the leaf is attached is approximately 5-7 mm long supporting an oblong leaf blade. The tree can be commonly found growing in mountain forests and valley thickets from an elevation of 200 to 1000 meters. The tree is native to India, Indonesia, Laos, Malaysia, Myanmar, Philippines, Thailand, Vietnam, and Northern Australia. Within the regions where the plant is found the indigenous population has used the entirety of the plant for various reasons. Such uses include, utilizing the roots and leaves for the treatment of injury and cuts, the fruits to cure pulmonary tuberculosis, and extracting a blue dye from the leaves.